Glauber cross sections for arbitrary excitation of ground-state hydrogen by electron and proton impact

Journal Article · Sun Feb 01 04:00:00 EST 1981 · Phys. Rev., A; (United States)

DOI:https://doi.org/10.1103/PhysRevA.23.715· OSTI ID:6917411

Sur, S K; Sil, N C

The Glauber scattering amplitude for 1s-nlm excitations of hydrogen by charged particle impact is reduced to a form numerically computable for arbitrary values of n, l, and m. The increasing number of repeated parametric differentiations appearing in earlier methods with the increase of n is replaced in our method by a single contour integration, which is especially useful for large-n states. In addition, whereas the available closed-form expressions would involve the calculation of a large number of hypergeometric functions as l and m increase for a given n, the present integral form involves only one hypergeometric function for any n, l, and m. The asymptotic form of the 1s-nlm amplitude as n..-->..infinity is also presented. The procedure is applied for studying the 1s..-->..ns (n=3, 4, 10, and infinity) and 1s..-->..np (n=3, 4, and infinity) excitations of hydrogen by electron and proton impact. Tabular results of the cross sections are presented for differential and integrated cross sections in e/sup -/-H collisions and for integrated cross sections in H/sup +/-H collisions. The qualitative features observed earlier for low ns and np excitations are found to exist also for n> or =3 excitations. The 1s..-->..ns and 1s..-->..np cross sections obey an n/sup -3/ law asymptotically as n/sup -2/..-->..0, which is in conformity with the analytical results obtained quite generally for 1s..-->..nlm excitations. For proton impact 1s3chemically bond3p excitations, the Glauber results are in excellent agreement with a recent 34-state calculation.

• Research Organization: Department of Theoretical Physics, Indian Association for the Cultivation of Science, Jadavpur, Calcutta 700 032, India
• OSTI ID: 6917411
• Journal Information: Phys. Rev., A; (United States), Journal Name: Phys. Rev., A; (United States) Vol. 23:2; ISSN PLRAA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
AMPLITUDES
ATOM COLLISIONS
CATIONS
CHARGED PARTICLES
COLLISIONS
CROSS SECTIONS
DIFFERENTIAL CROSS SECTIONS
ELECTRON COLLISIONS
ELECTRON-ATOM COLLISIONS
ELEMENTS
ENERGY-LEVEL TRANSITIONS
EXCITATION
GLAUBER THEORY
HYDROGEN
HYDROGEN IONS
HYDROGEN IONS 1 PLUS
INTEGRAL CROSS SECTIONS
ION COLLISIONS
ION-ATOM COLLISIONS
IONS
NONMETALS
SCATTERING AMPLITUDES